1. Welcome
to the
States of Matter
HMMM?

2. The Kinetic Molecular Theory
Introduction to the Kinetic Molecular Theory

3. Gas particles are small, hard spheres with a small volume.
13.1
According to kinetic theory:
Gas particles are small, hard spheres with a small volume.
Gases are in constant, random, straight line motion
Collisions are elastic

4. Kinetic Theory and a Model for Gases
13.1
Kinetic Theory and a Model for Gases
Some Facts About Kinetic energy
energy of motion
ALL matter is in motion
ALL matter has kinetic energy
Higher temperature = more kinetic energy

5. (but not liquids or solids)
Compressibility
Cool Property of Gases
(but not liquids or solids)
Compressibility
Measure of how much the volume of matter decreases under pressure.
Large distance between gas molecules
A crash dummy can be used to test the effectiveness of an air bag. Because gases can be compressed, the air bag absorbs some of the energy from the impact of a collision. Air bags work best when combined with seat belts.

6. Factors Affecting Gas Pressure
Variables Related to Gases
pressure (P) in kilopascals or atm
volume (V) in liters or milliliters
temperature (T) in kelvins (add to to °C)
the number of moles (n).

7. Common Pressure Conversions
The SI unit of pressure is the pascal (Pa).
Common Pressure Conversions
1atm = 101,325 Pa = kPa = 760torr = 760 mmHg

8. Complete the following conversions
1.3 atm to KPa
789mmHg to atm
890.5torr to atm
2.5 atm to Pa and Kpa
670mmHg to torr

9. Introduction to the Gas Laws
Boyles Law – pressure and volume
Charles Law – temperature and volume
Gay-Lussac’s – pressure and temperature

10. Boyle’s Law: Pressure and Volume
If the pressure of a gas increases, the volume decreases.
Indirect relationship

11. Factors Affecting Gas Pressure
Volume
If you…
Decrease the volume(push down on the bike pump)
Less room for the gas
Hits the sides more often
Increases the pressure

12. Factors Affecting Gas Pressure
When the volume of the container is halved, the pressure the gas exerts is doubled.
A piston can be used to force a gas in a cylinder into a smaller volume. When the volume is decreased, the pressure the gas exerts is increased. Interpreting Diagrams What happens to the gas pressure when the volume is reduced from 1 L to 0.5 L?

13. Click to Run Boyles Law Simulation

14. Charles’s Law: Temperature and Volume
As the temperature of a gas increases, the volume increases.
Direct Relationship

15. Charles’s Law: Temperature and Volume
As the temperature of the water increases, the volume of the balloon increases.
When the gas in the blue balloon is cooled at constant pressure, the volume of the gas decreases. When the gas is heated at constant pressure, the volume increases. Calculating What is the ratio of volume to temperature for each set of conditions? Round your answer to two significant figures.

16. Charles’s Law: Temperature and Volume
Charles Law – Volume Temperature
properties

17. Gay-Lussac’s Law: Pressure and Temperature
As the temperature of a gas increases, the pressure increases.
Direct Relationship

18. Factors Affecting Gas Pressure
Temperature
If you…
Increase the temperature
Increases the kinetic energy
Molecules move faster
Hit the sides more often
Increases the pressure

19. Gay-Lussac’s Law: Pressure and Temperature
When a gas is heated at constant volume, the pressure increases.
When a gas is heated at constant volume, the pressure increases. Interpreting Diagrams How can you tell from the drawings that there is a fixed amount of gas in the cylinders?

20. A Cool Model to Start Us Off
More About
States of Matter

21. What You Should Learn
Recognize solids have stronger attractive forces than liquids and liquids have stronger forces than gases.
Recognize solids have more ordered arrangement than liquids or gases.
Explain why ionic solids melt at higher temperatures than covalent solids.
Describe states of matter in terms of motion and arrangement of molecules or atoms.

22. Focus on Liquids

23. Fluid – any substance that flows
13.2
A Model for Liquids
Fluid – any substance that flows
Liquid Gas
Both liquids and gases can flow. The liquid on the left is colored water. The gas on the right is bromine vapor. If a gas is denser than air, it can be poured from one container into another. These pictures were taken in a fume hood because bromine is both toxic and corrosive. Predicting Over time, what will happen to the gas in the uncovered beaker? Explain.

24. Stronger attractions than gases
13.2
A Model for Liquids
Stronger attractions than gases
Less space between molecules
Denser than a gas

25. Model of a Liquid
A quick Video

26. Orderly arrangement of atoms/molecules Fixed, vibrating in position
13.3
A Model for Solids
Focus on Solids
Orderly arrangement of atoms/molecules
Fixed, vibrating in position

27. 13.3
A Model for Solids
The melting point (mp) is the temperature at which a solid changes into a liquid.
A Video

28. Ionic Compounds Covalent Compounds
Metal + Nonmetal
Nonmetal + Nonmetal
Very strong attractive forces
Weak attractive forces
Mostly solid at room temperature
Mostly gases at room temperature
High melting point
Low melting point

29. A States of Matter Simulation